The section setting the case
initialization discussed starting a new case as a branch run or
hybrid run by using data from a previous run. First you need to create
a new case. Assume that $CCSMROOT is set to /user/ccsmroot and that
$EXEROOT is /glade/scratch/$user/EXAMPLE_CASEp. Finally,
assume that the branch or hybrid run is being carried out on NCAR's
IBM system, bluefire.

For a branch run, env_run.xml for EXAMPLE_CASEp should be
identical to EXAMPLE_CASE, except for the $RUN_TYPE setting. In
addition, any modifications introduced into
~/cesm1/EXAMPLE_CASE/user_nl_cam,
should be re-introduced into the user_nl_cam file in EXAMPLE_CASEp.

Set up and build the case executable.

> ./cesm_setup -case
> ./EXAMPLE_CASEp.build

Prestage the necessary restart/initial data in $RUNROOT
(assumed to be /glade/scratch/$user/EXAMPLE_CASEp/run). Note
that /glade/scratch/$user/EXAMPLE_CASEp/run was created
during the build. Assume that the restart/initial data is on the NCAR
HPSS.

It is assumed that you already have a valid load-balanced scenario.
Go back to the case directory, set the job to run 12 model months, use an
editor to change the time limit in the run file to accommodate a 12-month
run, then submit the job.